 | George Nader als Roy |
 | Claudia Barrett als Alice |
 | Gregory Moffett als Johnny |
 | John Mylong als The Professor |
 | Selena Royle als Mother |
 | Pamela Paulson als Carla |
 | George Barrows als Ro-Man the Monster / Great Guidance |
 | John Brown als Ro-Man / Great Guidance (voice) |
| Phil Tucker | Director |
| Phil Tucker | Producer |
| Elmer Bernstein | Original Music Composer |
| Jack Greenhalgh | Director of Photography |
| Merrill G. White | Editor |
| Wyott Ordung | Screenplay |
| Alan Winston | Associate Producer |
| Al Zimbalist | Executive Producer |
| Stanley E. Campbell | Makeup Artist |
| Clarence Eurist | Production Supervisor |
| Robert E. Barnes | Assistant Director |
| John Orlando | Property Master |
